Multiple sliding doors and frame for tanning drums and the like



March 19, 1957 L TIGERMAN 2,785,562

MULTIPLE SLIDING DOORS AND FRAME FOR TANNING DRUMS AND THE LIKE 2 Sheets-Sheet 1 Filed May 3, 1956 INVENTOR.

36 Lows 'l' eezuwa vwuv ATTORNEY March 19, 1957 L. TIGERMAN 2,785,562 ANNING MULTIPLE SLIDING DOORS AND FRAME FOR T DRUMS AND THE LIKE Filed May 3, 1956 2 Sheets-Sheet 2 INVENTOR. \eeRmaN LouIs T FIG. '7

ATTORNEY United States Patent 2,785,562 MULTIPLE SLIDING DOORS AND FRAME FOR TANNING DRUMS AND THE LIKE Louis Tigerman, Milwaukee, Wis., assignor to Pfister &

Vogel Tanning Company, Milwaukee, Wis., a corporation of Wisconsin Application May 3, 1956, Serial No. 582,376 9 Claims. (Cl. 69-30) This invention relates to multiple sliding doors particularly suited for use in leather tanning drums or other like revolving cylinders wherein materials are tumbled in a solution, the solution removed, the material washed and then removed.

in such drums solid doors and wash doors are alternately locked in closing position on the loading doorway. Such doors are also subject to the action of the acids and alkalis used in various treating solutions.

It is an object of this invention, therefore, to provide doors for such use which are easily moved into and out of closing position on the doorway and quickly locked in closed position.

Another object of this invention is to provide doors for such use which will not warp, become water logged or damaged by the treating solutions.

A further object of this invention is to provide a wash door for such use which permits the maximum discharge of fluids while retaining the material being treated.

Still another object of this invention is to provide a solid door for such use which makes a tight uniform seal for its entire periphery.

A final object of this invention is to provide a doorway frame which is characterized by its cooperation with drum hands to keep the drum in true shape.

In the accomplishment of these objects a pair of arcuate plastic doors are slidably mounted within the drum between tracks. Such tracks extend along one pair of opposite sides of and project beyond the other pair of opposite sides of the doorway far enough to hold the doors within the drum beyond the confines of the doorway. Either door can be easily slid on said tracks into and out of doorway closing position. The door in operative position is drawn against the inner face of the drum by wing screws rotatively mounted in a clamp bar spanning the doorway and threadedly engaged with the door. The tracks hold the door so that it is easy to quickly apply the clamp bar. Pivoted tongues on the sides of the doorway hold the door in inoperative position for loading and unloading the drum. The solid door in particular has the radius of its outer arcuate surface greater than the radius of the inside of the drum, hence such door is slightly deflected or sprung when clamped. This maintains a tight seal along the sides most remote from the winged clamp ing screws and makes the seal uniform throughout the periphery of the door. Since both doors are formed from plastic material, they are not afiected by the action of the treating solutions, will not become water logged and will not warp. The wash door in addition to the drain holes therein has outwardly projecting pads at its corners which space the door from the inner face of the drum to provide additional drainage openings along its sides with a large sectional area but narrow enough to prevent loss of the hides or other materials being treated. The doorway is framed by opposite Zs tied together at the ends so that at least one drum band may encircle the drum between the sides of the doorway and be drawn tight by threaded nuts bearing against the projecting flanges of such Zs.

One embodiment of this invention is set forth in the following description and shown in the accompanying drawings, in which: j j

Fig. 1 is a view in top elevation of a leather tanning drum with a doorway and multiple sliding doors embodying this invention;

Fig. 2 is an enlarged sectional view taken on the line 22 of Fig. 1 with the washing door in operative position with respect to the doorway;

Fig. 3 is a view similar to the view of Fig. 2 with the solid door closing the doorway;

Fig. 4 is a top plan view of the arcuate plastic solid door for sealing the doorway;

Fig. 5 is a top plan view of the arcuate plastic wash door for the doorway;

Fig. 6 is an enlarged fragmentary sectional view similar to the views of Figs. 2 and 3 with both doors in inoperative position on each side of the doorway;

Fig. 7 is an enlarged fragmentary sectional view taken on the line 77 of Fig. 3; and

Fig. 8 is an enlarged fragmentary View in side elevation taken from the line 8-8 of Fig. 6.

To illustrate the invention the doorway and multiple sliding doors embodying such invention are shown as used with a wooden tanning drum 10 of usual design with its staves held by encircling stainless steel bands 12, 14 and 17. Such drum revolves on trunnions through which the leather tanning solutions and washing water are introduced. A rectangular doorway 16 is provided in the drum for the charging and discharging of hides. The rectangular shape permits the doors to be inserted into and withdrawn from the interior of the drum. The sides of bands 14 are alined with the ends of the doorway 16 to form part of the metal frame. Stainless steel Zs 18 extend along the sides of the doorway 16 with one flange against such sides and the other flange projects radially from the drum. The ends of the Zs 18 are welded to the bands 14 to make a solid frame. Hence a split stainless steel band 17 may encircle the drum 10 between the ends of the doorway 16 and be secured by adjustable means 19 to the outer flanges of the Zs 18. This permits strengthening of the drum as if the doorway were not present and is an advantage. On the inside of the drum 10 in juxtaposition with the Web of the Zs 18 are brass backing strips 20 secured to such Zs by bolts and nuts 22. These strips form part of the seal between door and doorway. Also mounted within the drum 19 in juxtaposition with the bands 14 are a pair of brass tracks 24. The confronting edges of these tracks are alined with ends of the doorway 16 to also form another part of the seal between door and doorway. They extend beyond the sides.

of the doorway to form door storage space as hereinafter described. The bands 14 and the tracks 24 are clamped together by countersunk bolts and nuts 26. Another pair of brass tracks 28 are mounted within the drum with their confronting edges alined with the edges of the doorway 16 and the confronting edges of the tracks 24. The tracks 28 are wide enough so that they are carried on wooden spool spacers 32 placed adjacent the tracks 24, both the tracks and spacers being held in place by countersunk bolts and nuts 34 extending through such tracks, spacer and drum. The spacing between the tracks 28 and the tracks 24 is sufiicient to permit the doors to be slidably held therebetween and laterally guided by such spools. The ends of the tracks 24 and 28 terminate at wooden stops 36 which are spaced from the sides of the doorway 16 a snflicient distance to store a door on each side of such doorway and still provide for the closing of the doorway by either of the doors in the manner hereinafter described. The tracks 23 have removable sections 30 opposite the doorway 16 to permit doors to be mounted between the tracks 24 and 28 and slid to inoperative storage position until the sections 30 have been replaced.

Slidably mounted between the tracks 24 and 28 is an arcuate plastic solid door 38 and an arcu-ate plastic wash door 40. These doors are identical in size and shape and vary only in the differences hereinafter pointed out.

3 They are molded from a thermosetting resin such as melamine formaldehyde filled. This makes-a strong,- light-weight door which will. not absorb water and is inert to the tanning solutions used in the drum. Each door has a peripheral supporting flange 42 andspaced supporting ribs 44, the latter extending from side to side of the doors. Centrally located in these ribs and molded therein are threaded metal blocks 46 having bearing plates 48. They are open to the outside of the doors to threadably receive wing bolts 50 and are covered on the inside. The doors, when in operative position, are clamped against the inside of the drum 1% by such bolts passing through and bearing against a clamp bar 52 ex-' tending from end to end of the doorway 16.

The radius of the arcuate outer surface of the solid door 38 (for manufacturing economies only this may be true of-the wash door) is greater than the radius of the inner surface of the drum so that it is necessary to deflect such door in the neighborhood of one-half inch to make a tight seal between its sides and the sides of the doorway 16. This deflection assures pressure at the sides remote from the clamping action of the wing bolts 50. The clamp bar 52 is unattached to the drum and is removed when the wing bolts 50 are unthreaded from the door thus making the doorway 16 unobstructed. The solid door 38 has a felt seal 54extending completely around its periphery on the outer surface. This seal, when the door is clamped, seats against the tracks 24 and strips to make a substantially water-tight closing of the doorway 16. In order to have means for holding the solid door 38 While removing it from the drum, it is preferable to have a pair of internally threaded metal inserts 56 into which lifting hooks (not shown) can be threaded. The wash door 4% has a multiplicity of spaced holes 58 to permit drainage of water and tanning solution while retaining the hides within the drum. Additional drainage space is obtained by applying felt pads 60 at each of the corners on the outer surface of the wash door 40. These pads hold the door spaced from the face of the tracks 24 and strips 20 and thus there is formed a long narrow opening 62 which also permits the discharge of washwater and other fluids while retaining the hides. A pair of tongues 64 loosely mounted on studs 66 projecting inwardly from the Zs 2t) and secured in either'operative or inoperative positionby wing nuts 68. These tongues, as shown in Fig. 6, are placed in operative position to keep both of the doors 3% or do in the out-ofway position for loading and unloading of the drum. One may be used to keep one door out of the way when another is being removed from the drum. However, it is the door in operative position with respect to the doorway 16 which holds the other door in the inoperative stored position and not such tongues.

With thedoors slidably mounted, as described herein, the drum is loaded when the doors are held on opposite sides of the doorway 16, as shown in Fig. 6. After loading the solid door 36 is slid into operative position with respect to the doorway 36 (see Fig. 3), the clamp bar 52 assembled and the wing bolts tightened to draw the seal 54 tightly against the strips 20 and tracks 24. The wash door 40 is now securely held in storage position within the drum 10 between the wooden stop 36 and the clamped solid door 38. After proper rotation of the drum, it is stopped, the wing bolts 50 and clamp bar 52 are removed and the solid door 33 slid to inoperative position and the wash door dd slid to operative position, see Fig. 2.. The clamp bar 52 and wing bolts 50 are then put in place again and the drum is ready for rotation during a draining and washing cycle. The dye and wash water will escape through the openings 58 and through the long narrow opening 62. each time the doorway 16 goes through the lower half of the cycle of the drum. To remove the hides, the wing bolts 50 and clamp bar 52 are removed and the wash door 40 slid to the other side of the doorway 16 and both tongues 64secu'red in the retaining position shown in Fig. 6. The drum is then rotated until the doorway is on the bottom.

In order to change a damaged door or to initially install the doors, the three central bolts 34 are removed and the sections 30 are taken out of the drum. The solid door may then he slid until the inserts 56 register with the doorway 16. Hooks or other holding devices are screwed into such inserts and hold the door as it is slid into juxtaposition with the doorway 16. Thereafter the door is lowered and turned through to aline its ends with the sides of the doorway 16 for removal from the drum. The same steps are used for the removal of the wash door id with the exception that holding hooks are inserted in the openings 58 instead of threaded inserts iike those in the solid door.

I claim:

1. In a treating and washing drum having a doorway, a pair of doors slidably mounted within said drum and movable alternately into and out of doorway closing position, and means external of said drum to clamp the door in doorway closing position.

2. The combination as claimed in claim 1 in which the door in doorway closing position holds the other door in storage position next to such doorway.

3. In a drum having a doorway, a door within said drum having an arcuate outer face and peripheral margin seating against the inner face of said drum about said doorway, said arcuate outer face having a radius greater than the radius of the inner face of said drum, and means engaging said door intermediate its sides to pull said door against the inner face of said drum and deflect said drum to provide sealing pressure along said sides.

4. In a leather tanning drum having a doorway, a door mounted within said drum and held against the inner face thereof, said door being molded of plastic material inert to the leather tanning solutions within said drum and impervious to water.

5. The combination as claimed in claim 4 in which said door has internal reinforcing ribs and threaded metal inserts molded therein and accessible only from the outer side of said door. i

6. In a drum having a doorway, a wash door within said drum covering said doorway, said door having a multiplicity of drainage holes through the face thereof, and projections on the corners of said door spacing the edges of said door from the inner face of said drum to provide narrow and long drainage openings.

7. In a drum having a doorway, a metal frame for said doorway having axially extending Zs with inner flanges resting against the sides of said doorway and outer flanges projecting from the outer face of said drum, said frame having circumferentially extending bands secured to'the ends of said Zs, and a slit drum band encircling said drum with its ends adjustably secured to said outer flanges intermediate the ends thereof.

8. In a leather tanning drum having a doorway, a pair of tracks mounted within said drum and extending along the ends of said doorway and projecting beyond both sides ofsaid doorway, a second pair of tracks mounted within said drum' in alinement with and spaced from said first pair of tracks, spacing spools holding said second pair of tracks so spaced and providing lateral guides, a solid door and a wash door both slidably mounted between said tracks, stoppers at the ends of said tracks spaced far enough from said doorway to hold one door on one side of said doorway between a stopper and the other door clamped in closing position on said doorway, and means for clamping the door in place on said doorway.

9. The combination as claimed in claim 8 in which said second pair of tracks has sections opposite said doorway removable to provide an opening for withdrawing said doors from said tracks. i

No references cited. 

